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Finding the Fourth Proportional to 604.20, 905.34 and 387.60

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Solution

The fourth proportional to 604.20, 905.34 and 387.60 is: 580.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    604.20 : 905.34 = 387.60 : x
  2. Step 2: Convert to fraction form
    604.20/905.34 = 387.60/x
  3. Step 3: Cross multiply
    604.20x = 905.34 × 387.60
  4. Step 4: Simplify right side
    604.20x = 350,909.78
  5. Step 5: Solve for x
    x = 350,909.78/604.20
  6. Step 6: Final answer
    x = 580.78

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.